Wearable face mask with anti-viral filtration media

ABSTRACT

A mask assembly, including a face covering portion, a pocket connected to the face portion and positioned to cover a wearer&#39;s nose and mouth, a connection portion operationally connected to the face covering portion, and a filter removably inserted in the pocket. The filter further includes a porous hydrophobic and lipophobic layer, a diamond-like carbon layer, an activated carbon layer, an N95 membrane, an anti-stick cloth layer, and a non-woven fabric layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority to co-pending U.S. Provisional Patent application Ser. No. 63/007,012, filed on Apr. 8, 2020.

TECHNICAL FIELD

The present disclosure relates generally to the field of medicine and, more particularly, to a novel method and system for preventing exhaled viral particles from infecting others.

BACKGROUND

This section introduces aspects that may help facilitate a better understanding of the disclosure. Accordingly, these statements are to be read in this light and are not to be understood as admissions about what is or is not prior art.

The need for better facemask protection against airborne pathogens has been brought into focus by the ongoing COVID-19 pandemic. The general public, as well as front-line health care providers, are at risk to be infected in many cases for lack of proper equipment. Infectious viruses are carried in airborne droplets produced by sneezing, coughing, and talking. Aerosolized SARS coronavirus droplets range in size from 0.1 to 8 μm, which can survive in the ambient environment for a couple of days. While larger droplets or particles (>50 μm) settle on the ground very quickly, medium sized particles (10-50 μm) remain airborne for minutes and smaller particles (<10 μm) can remain airborne for hours and are easily inhaled into the respiratory tract. N95 medical grade masks are the current ‘gold standard’ for personal protection, but while N95 masks typically are 90-95% efficient in filtering breathing air, prolonged exposure to airborne pathogens (such as is the case with medical responders) will eventually result in pathogens breaching the mask.

Thus, there remains an unmet need for better personal protective masks that better eliminate exposure to harmful airborne pathogens, The present invention addresses this need.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A-1C are perspective views of a different masks.

FIG. 2A-2C are perspective views of a filter according to the present novel technology being inserted into a mask having a receiving slot.

FIG. 3 is an exploded view of the filter of FIGS. 2A-2C.

FIG. 4 schematically illustrates the functionalization of polypropylene cloth.

FIG. 5A-5D schematically illustrates siloxanization of functionalized polypropylene cloth.

FIG. 6 graphically illustrates the destruction of pathogens in contact with the antipathogen layer of the filter of FIGS. 2A-2C.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of the claimed technology and presenting its currently understood best mode of operation, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, with such alterations and further modifications in the illustrated device and such further applications of the principles of the claimed technology as illustrated therein being contemplated as would normally occur to one skilled in the art to which the claimed technology relates.

The present novel technology relates to a multilayer mask assembly 10 and an interchangeable filter 30 for use in the multilayer mask assembly 10, as well as in other mask designs, so as to enhance the mask protective capabilities again airborne pathogens, viral agents, and particles.

The mask assembly 10 includes a face covering portion 15, an attachment portion 20, and a filter-receiving portion 25 for holding a filter 30 in the face covering portion 15. The filter receiving portion 25 is positioned so as to cover the nose and/or mouth of the wearer such that inhalation and exhalation forces air through a filter 3—inserted into the filter-receiving portion 25.

The attachment portion 20 may be one or more elastic or nonelastic straps connected to the face covering portion 15 for connection to the wearer's head, such as by hooking around the ears or encircling the head. The attachment portion 20 may also be unitary with the face covering portion 15, such as with scarves or scarf-like masks.

The filter-receiving portion 25 is typically a slot or pocket formed in the face covering portion 15, sized and shaped to snugly to engage the filter 30, such as in an interference or like fit. In some embodiments, the filter 30 includes an adhesive portion 35 for better connection of the filter 30 to the filter-receiving portion 25. Likewise, filter 30 may include hook or loop type connectors 35 for matingly engaging loop or hook type connectors 30 positioned on the mask 10. In some embodiments, the filter-receiving portion 25 is simply the area of the mask 10 directly covering the nose and mouth of the wearer, and the filter 30 includes adhesives or fasteners 35 for engaging the mask fabric. This is especially helpful for using the filter 30 with a generic cloth or like material mask.

The filter 30 is typically assembled as a multilayer or stacked composite material. In some embodiments, the outermost layer 40 (positioned farthest from the wearer) is composed of a porous hydrophobic and lipophobic material. The next layer 45 is a doped diamond-like carbon (DLC) layer, followed by an activated carbon layer 50, an N95 membrane 55, a layer of anti-stick cloth 60, and a non-woven fabric layer 65. This composite stack of layers is mounted in a foldable frame 75.

The outer porous hydrophobic and lipophobic layer 40 is prepared by functionalizing a polypropylene fabric. The polypropylene fabric is functionalized in a 2-step process. First, production of —OH groups on the surface of the polypropylene surface is accomplished by reacting the fabric in an aqueous solution of K2S2O8 at 80° C. under N2 reflux. Next, the now-hydroxylated polypropylene surface is reacted with siloxane, resulting in the entirety of the surface of the fabric being chemically attached to siloxane molecules. It should be noted that this chemical bonding of siloxane to the polypropylene fabric is more then mere impregnation and thus is not easily removed.

The DLC layer 45 is a biocompatible matrix that is doped or otherwise impregnated with antipathogen agents 70 such as zinc oxide clusters, metallic silver, and/or the like. The DLC layer 45 is also hydrophobic, and so prevents the transmission of any micro-droplets of water that may have made it through the outer layer 40. Because the DC layer 45 is biocompatible, the user is not at risk for any particles of DLC that may contact the user.

The activated carbon layer 50 and the N95 layer 55 serve to capture and contain particulate matter making it through the outer layers 40, 45. This extra air filtration allows for the stoppage of particles passing through the outer layers 40, 45 during inhalation, and also for the reintroduction of those stopped particles to the antipathogens in the DLC layer 45 during exhalation, cycling particles within the filter 30 to further increase the likelihood of pathogen deactivation and/or not ever passing through to the user, which likewise decreases the likelihood of the user experiencing infection. The inner non-stick and nonwoven layers 60, 65 function to prevent the filter 30 from adhering to the wearer, further decreasing the likelihood of infection from pathogens.

Tape or like adhesive, hooks, hook and loop connectors, or like connection members 35 may be operationally connected to the edges and corners of the filter 30, such as a frame 75 surrounding the respective filter layers 40 45, 50, 55, 60, 65, to allow attachment of the filter 30 to most masks, including bandanas and scarves. In one exemplary embodiment, filters 30 are provided at fifty to a box, along with three basic cotton white masks 10 that may be regularly washed. After each use, the used filter 30 is removed and discarded and a new filter 30 is inserted or otherwise attached to the mask 10. The filter 30 includes an N95 layer 55, as is typically required for use in hospitals, and an anti-bacterial/anti-viral layer 45 to kill pathogens. In one embodiment, the anti-pathogenic layer 45 includes impregnation with silver and zinc oxide 70; in other embodiments, other anti-pathogenic agents 70 may be elected. The anti-pathogenic layer 45 may be tailored for one or more expected pathogens. The superhydrophobicity/lipophobicity of the outer layer 4-0 operates to prevent pathogens from further penetrating the filter 30, while the anti-pathogenic layer(s) 45 operate to kill any pathogens that manage to make it past the outer layer 40, making the likelihood of pathogenic intake through the filter 30 significantly lower and thus reducing the probability of infection from incoming virus particles. The series of membranes and filters 50, 55, 60, 65 after the intake covered with the DLC 45 prevent other particles from passing into the lungs. Notice that a membrane is integrated to the main filter 30 to finally have an anti-stick filter layer 60 and one non-woven fabric layer 65 that acts as the last layer before the user is reached.

In some embodiments, the filter 30 includes multiple layers of at least one of the filter materials 40, 45, 50, 55, 60, 65. In other embodiments, the order of the filter layers 40, 45, 50, 55, 60, 65 may be varied.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character. It is understood that the embodiments have been shown and described in the foregoing specification in satisfaction of the best mode and enablement requirements. It is understood that one of ordinary skill in the art could readily make a nigh-infinite number of insubstantial changes and modifications to the above-described embodiments and that it would be impractical to attempt to describe all such embodiment variations in the present specification. Accordingly, it is understood that all changes and modifications that come within the spirit of the invention are desired to be protected. 

1. A mask assembly, comprising: a face covering portion; a pocket connected to the face portion and positioned to cover a wearer's nose and mouth; a connection portion operationally connected to the face covering portion; and a filter removably inserted in the pocket; wherein the filter further comprises: a porous hydrophobic and lipophobic layer; a diamond-like carbon layer; an activated carbon layer; an N95 membrane; an anti-stick cloth layer; and a non-woven fabric layer.
 2. The mask assembly of claim 1 wherein the porous hydrophobic layer is a hydroxylated polypropylene surface having chemically attached siloxane molecules.
 3. The mask assembly of claim 1 wherein the diamond-like carbon layer is impregnated with clusters selected from the list consisting of zinc oxide, metallic silver, and combinations thereof.
 4. The mask assembly of claim 1 wherein the outermost filter layer is the porous hydrophobic layer, followed immediately by the diamond like carbon layer; wherein the activated carbon layer is positioned between the diamond like carbon layer and the N95 membrane; and wherein the anti-stick cloth layer is positioned between the N95 membrane and the non-woven fabric layer.
 5. The mask assembly of claim 1 wherein the filter includes multiple layers of at least one material.
 6. The mask assembly of claim 1 wherein the filter further comprises a connector for attaching the filter to the face covering portion.
 7. The mask assembly of claim 6 wherein the connector is selected from the group consisting of tape, adhesive, hooks, and hook and loop connectors.
 8. The mask assembly of claim 1 wherein the filter further comprises a frame portion for supporting multiple filter layers.
 9. A mask, comprising: a face covering portion; a connection portion operationally connected to the face covering portion; and a filter attachable to the face covering portion; wherein the filter further comprises: at least one porous hydrophobic and lipophobic layer; at least one diamond-like carbon layer; at least one activated carbon layer; at least one N95 membrane; at least one anti-stick cloth layer; and at least one non-woven fabric layer.
 10. The mask of claim 9 wherein the porous hydrophobic layer is a hydroxylated polypropylene surface having chemically attached siloxane.
 11. The mask of claim 9 wherein the diamond-like carbon layer is impregnated with clusters selected from the list consisting of zinc oxide, metallic silver, and combinations thereof.
 12. The mask of claim 9 wherein the outermost filter layer is the porous hydrophobic layer, followed immediately by the diamond like carbon layer; wherein the activated carbon layer is positioned between the diamond like carbon layer and the N95 membrane; and wherein the anti-stick cloth layer is positioned between the N95 membrane and the non-woven fabric layer.
 13. The mask of claim 9 wherein the filter further comprises a connector for attaching the filter to the face covering portion.
 14. The mask of claim 13 wherein the connector is selected from the group consisting of tape, adhesive, hooks, and hook and loop connectors.
 15. The mask of claim 9 wherein a pocket is formed in the face covering portion for holding the filter.
 16. A filter comprising: at least one porous hydrophobic and lipophobic layer; at least one diamond-like carbon layer; at least one activated carbon layer; at least one N95 membrane; at least one anti-stick cloth layer; and at least one non-woven fabric layer.
 17. The filter of claim 16 and further comprising a frame portion operationally connected to hold the respective layers; and a connector operationally connected to the frame portion for connecting the filter to a mask. 